Nervous System AP Biology 2003 -2004
Why do animals need a nervous system? § What characteristics do animals need in a nervous system? u fast u accurate u reset quickly Remember… think about Poor bunny! the bunny… Regents Biology 2003 -2004
Nervous System cerebrum cerebellum spinal cord § Central nervous system u brain & spinal chord § Peripheral nervous system nerves from senses u nerves to muscles u cervical nerves thoracic nerves lumbar nerves femoral nerve sciatic nerve tibial nerve Regents Biology 2003 -2004
Nervous system cells § Neuron signal u direction a nerve cell dendrites cell body axon signal direction synapse Regents Biology 2003 -2004
Fun facts about neurons § Most specialized cell in § animals Longest cell u blue whale neuron § 10 -30 meters u giraffe axon § 5 meters u human neuron § 1 -2 meters Nervous system allows for 1 millisecond response time Regents Biology 2003 -2004
Myelin sheath signal direction § Axon coated with insulation made of myelin cells u speeds signal § signal hops from node to node u Multiple Sclerosis § immune system (T cells) attacks myelin sheath Regents Biology § loss of signal 330 mph vs. 11 mph myelin sheath 2003 -2004
Synapse Junction between nerve cells u u 1 st cell releases chemical to trigger next cell this is where drugs affect nervous system Synapse Regents Biology 2003 -2004
§ http: //www. youtube. com/watch? v=HXx 9 ql. Jet. SU&list=PL 6 C 5 E 12 A 50 A 29788 F Regents Biology 2003 -2004
Types of neurons sensory neuron (from senses) interneuron (brain & spinal chord) Regents Biology motor neuron (to muscle) 2003 -2004
Simplest Nerve Circuit § Reflex, or automatic response rapid response § automated u signal only goes to spinal cord § no higher level processing u advantage § essential actions § don’t need to think or make decisions about § blinking § balance § pupil dilation § startle 2003 -2004 u Regents Biology
Eye Blink or Pain Withdrawal Reflex Gray Interneuron matter White matter Stimulus Sensory neuron Receptor in skin Motor neuron Spinal cord Regents Biology Effector 2003 -2004 (muscle)
§ Resting Potential = -70 millivolts § Many Na+ on the outside of the neuron § Many K+ on the inside of the neuron § Many large negatively charged ions Regents Biology 2003 -2004
§ Threshold voltage = -50 m. V ( Na+ start rushing in) Action Potential = +30 m. V § Na+ continue to rush in and the K + rush out § Wave of depolarization § Refractory period-no impulse can be sent § Na-K pump-reset resting potential Regents Biology 2003 -2004
Divisions of the Peripheral Nervous System Regents Biology 2003 -2004
Regents Biology 2003 -2004
Blood Brain Barrier § blue dye that tissues of the whole body EXCEPT the brain and spinal cord would turn blue § Functions Protects the brain from "foreign substances" in the blood that may injure the brain. u Protects the brain from hormones and neurotransmitters in the rest of the body. u Maintains a constant environment for the brain. u Regents Biology 2003 -2004
The ventricles of the brain are a communicating network of cavities filled with cerebrospinal fluid Regents Biology 2003 -2004
Central Canal Regents Biology 2003 -2004
Regents Biology 2003 -2004
White and Gray matter Regents Biology 2003 -2004
Cranial Nerves Regents Biology 2003 -2004
Spinal Nerves Regents Biology 2003 -2004
Human brain Regents Biology 2003 -2004
Primitive brain § The “lower brain” medulla oblongata u pons u cerebellum u § Functions u basic body functions § breathing, heart, digestion, swallowing, vomiting homeostasis u coordination of movement u Regents Biology 2003 -2004
Higher brain § Cerebrum hemispheres u left = right side of body u right = left side of body u § Corpus callosum u major connection between 2 hemispheres Regents Biology 2003 -2004
Division of Brain Function § Left hemisphere u u u “logic side” language, math, logic operations, vision & hearing details fine motor control § Right hemisphere u u “creative side” pattern recognition, spatial relationships, non-verbal ideas, emotional processing, parallel processing of information Regents Biology 2003 -2004
§ http: //www. youtube. com/watch? v=z 7 Tc ug. Wqya. I § http: //www. youtube. com/watch? v=lf. Gw s. Ad. S 9 Dc Regents Biology 2003 -2004
Cerebrum specialization § Regions of the cerebrum are § specialized for different functions Lobes frontal u temporal u occipital u parietal u Regents Biology 2003 -2004
Limbic system Controls basic emotions (fear, anger), involved in emotional bonding, establishes emotional memory Regents Biology 2003 -2004
§ Reticular formation § Electroencephalogram EEG § Slow wave sleep § REM sleep Regents Biology 2003 -2004
§ http: //www. youtube. com/watch? v=sa 3 v Ldx. YTQY § http: //www. youtube. com/watch? v=q. NTL Iv 8 JZA 0 Regents Biology 2003 -2004
Regents Biology 2003 -2004
§ Short Term memory u Lasts only a few minutes § Long Term memory u Lasts for weeks or years u To move from short term to long term: § Rehearsal § Emotional state § Association with old data Regents Biology 2003 -2004
Referred pain Regents Biology 2003 -2004
Sensation vs perception Figure 29. 1 p 586 Regents Biology 2003 -2004
Regents Biology 2003 -2004
Regents Biology 2003 -2004
http: //www. watchknowlearn. org/Video. aspx? Video. ID=39957&C ategory. ID=1885 http: //ed. ted. com/lessons/how-we-see-color-colm-kelleher http: //ed. ted. com/lessons/why-do-we-see-illusions-markchangizi HTTP: //WWW. MAYOCLINIC. CO M/HEALTH/LASIK-EYESURGERY/MM 00607 Regents Biology 2003 -2004
Regents Biology 2003 -2004
http: //www. wptv. com/dpp/news/local_news/wate r_cooler/amy-barber-cochlear-implant-videotoday-show-spotlights-the-moment-she-firsthears-her-family http: //www. hearinglink. org/howwehear Regents Biology 2003 -2004
Muscle Contraction § Nerve releases acetylcholine which § § causes the sarcoplasmic reticulum to release Ca++ bond with troponin which causes tropomyosin to pull away from actin binding sites. Myosin cross bridges go in and muscle contracts. Regents Biology 2003 -2004
Regents Biology 2003 -2004
Скачать презентацию Nervous System AP Biology 2003 -2004 Why
890f71b5f6908705e131799ddd7cabc4.ppt